Thank you for sharing your thoughts @ancapbarbie. I agree with many of the points you've made especially the part about active participation by more users. And I'd hope those users (stakeholders) vote with at least a fairly good understanding of Steem and why they might vote or not vote for each witness.

One thing to note, with the exception of the top 20 witnesses, witness rank is not important when it comes to how many blocks a particular witness is scheduled to create. So their average income of SP is not affected by having an inactive witness ahead of them on the list. Inactive witnesses essentially are inert unless the owner of the account reactivates it.

The scheduling mechanism of Steem for the backup witness slot is voting-stake-based. Imagine a theoretical network where you have 22 witnesses, with the 21st-ranked witness having 10 times the voting stake of the 22nd-ranked witness: The 21st witness would produce 10 blocks for every 1 produced by the 22nd.

Regarding your solutions, I appreciate that you've proposed some but I have to tear them apart a bit:

Set an expiration time for Witness votes. I'm sure smarter people than I can figure out a practical duration, but this would eliminate inactive accounts' votes still counting and would increase the incentive for active users to both make sure their votes count and make sure new users we onboard understand the importance of Witness voting. One month? Three? Whatever. I don't see any downside to this and potentially a huge upside.

This has some theoretical positives but overall it would be a bad thing for Steem to implement. The largest issue with witness vote expiration dates is that it reduces the amount of stake in STEEM Power needed to successfully attack the network's block producer list. Making the network less secure is not a good "feature" to add.

Make each Witness vote carry equal weight. You want to upvote your own comment on some shit meme for $500? Fine. You're a bloody shit-stain, but that's your prerogative. You want to throw 25 Megavests at an inactive witness just to prevent someone else from moving up? Ya, you're rigging the game because the system is structured to let you do so. If you sort the list by number of votes, the top 50 shifts around a bit but 11 of those are inactive. That's on us, folks. This seems like a reasonable solution.

This would be an even worse feature. It's obvious to anyone in the decentralized network field that opening the door to a sybil attack is a no-go. Steem is stake weighted because, while not perfect, making an attack prohibitively expensive is the best defense these networks have.